Here's the genuine GM replacement...
Here's the genuine GM replacement serpentine belt, tensioner (left) and idler pulley assembly, ordered from Corvette Central. It's a good idea to replace all three items at the same time.
Like all things mechanical, the serpentine belt tensioner and idler pulley on C5 engines will eventually wear, develop play, and require replacement. A slight squeaking noise coming from either the tensioner pulley or the idler pulley-or both-is a good indication that it's time to install new units.
Personally, I always prefer to be safe rather than sorry, so when it became necessary to replace the tensioner on my wife's C5 ragtop, I decided to replace the idler pulley and put on a new serpentine belt at the same time. My reasoning here was that if one element (the tensioner) had sufficient wear and required replacement, then the idler pulley couldn't be far behind. And even though the belt didn't look at all bad, this was the ideal time to install a new one, since the old one had to come off anyway to replace the pulleys. The belt, tensioner, and idler pulley were all ordered from Corvette Central (www.corvettecentral.com).
I decided to stow the old serpentine belt in the trunk of the C5, rather than throwing it away. It only weighs a few ounces and doesn't take up much room, so what's the harm in keeping it in the trunk? After all, you never know when an emergency might arise and it could save the day-if not for me, then maybe for some other Corvette owner on the side of the road that I might be able to rescue, right?
The only tools needed for this job are a 15mm combination wrench, a 15mm socket, and a ratchet. Replacing these three items isn't complicated, so even a novice wrench should be able to do it in well under an hour. Just follow the captioned pix and you'll breeze right through it.
| Corvette Central Parts List |
| Part # |
Description |
| 305133 |
'97-'04 Engine Drive Belt (Water Pump, Pwr. Steer., Alt.) |
| 305308 |
'97-'04 Idler Belt Pulley |
| 305124 |
'97-'00 Drive Belt Tensioner |
Tools Required: 15mm combination wrench, 15mm socket, and ratchet
Time Start To Finish: Under 1 hour
| Difficulty Index - 2 Wrenches |
| Anyone’s Project: no tools required | 1 Wrench |
| Beginner: basic tools | 2 Wrenches |
| Experienced: special tools | 3 Wrenches |
| Accomplished: special tools and outside help | 4 Wrenches |
| Professionals Only: send this work out | 5 Wrenches |
There's a factory sticker...
There's a factory sticker on top of the inner left front fender of C5s that shows the belt routing in case you need a reference, although the route the belt takes is pretty straight forward.
Standing on the driver side...
Standing on the driver side of the car, use the box end of the 15mm combination wrench to pull the nut on the tensioner pulley toward you. Doing this relieves tension on the belt so it can be slipped off and over the alternator pulley.
Once the belt is off the alternator...
Once the belt is off the alternator pulley, slip it off the other pulleys and remove it from the car.
The tensioner is held onto...
The tensioner is held onto the engine block with two 15mm bolts which are removed next. When the bolts are out, remove the tensioner.
The old tensioner is at the...
The old tensioner is at the left and the new unit is on the right. There should be absolutely no side play in the pulley on the tensioner. Mine had about 1/64 of an inch side play which indicated the end wasn't far off. A slight tell-tale squeaking sound from the tensioner pulley is what alerted me to the problem in the first place.
The old idler pulley is on...
The old idler pulley is on the left and the new replacement is on the right. Both this pulley and the one on the tensioner are sealed units that can't be lubricated, so when they start to wear there's no saving them-they must be replaced.
The new tensioner is installed...
The new tensioner is installed by inserting and tightening the two 15mm bolts to retain it. Make sure they're nice and tight.
You'll have to reach in with...
You'll have to reach in with your socket and ratchet to get to the 15mm bolt that holds the idler pulley in place (the arrow is pointing to it); for this reason, you'll want to make sure that the engine is cool so you don' have the discomfort of your arm rubbing against a hot radiator hose. The replacement pulley installs in the exact reverse of the procedure you used to take the old one off. Again, make sure this bolt is good and tight.
Once the new tensioner and...
Once the new tensioner and idler pulley is in place, thread the new serpentine belt around the alternator pulley through the path shown in the routing diagram so the only thing that the belt isn't around yet is the tensioner pulley.
Once again standing on the...
Once again standing on the driver side of the car, put the slack belt loop next to the tensioner pulley, put the box end of your 15mm wrench on the pulley nut and pull it toward you, then slip the belt over the tensioner pulley and release the wrench so the tension takes up any remaining slack in the belt.
That's it. Now make sure you...
That's it. Now make sure you didn't leave any tools, shop rags, or other foreign objects in the engine bay. Start her up and make sure you don't hear anything squeaking or rubbing (you shouldn't). Once everything checks out OK, close the hood and you're done. See, I told you it wasn't hard, right?